As the saying goes, you can depend on Americans to do the right thing when they have exhausted every other possibility. (Not by Churchill [1].) Plus, it's not a given that it is the right thing to do, especially if there's no plan for what comes after; and there reportedly are early signs of social unrest on this side of the pond [2]. A shutdown can't last until there's a vaccine. At best it buys you time.
That's the very point. It takes some (or a lot of) burden off the health infra. Lockdown is being done in many countries so that not everybody will need hospitalisation at the same time.
Sure, but for how long will it remain sustainable? The lockdown hasn't lasted a month in Italy and they're already seeing early signs of food theft that could potentially degenerate into food riots. I'm struggling to imagine how any country will make it sustainable for more than a month or two. Yet on paper, a prerequisite for stopping the lockdown seems to be that you've been testing on a fairly large scale, which only Korea seems to have pulled off.
The situation in France, for instance, is unenviable at the moment and absolutely not sustainable: albeit to a lesser degree as in the US, there's not enough PPE for essential staff, not enough masks for everyone else, and most crucially not enough tests to go about. Yet there's a full lockdown with fines and all, and insofar as I'm aware there isn't enough financial help for employers or employees or the self-employed or anyone else. It's only a matter of time before everyone realizes that they're going into this like it's 1914, expecting it'll all be over by the autumn.
It won't.
It won't, because of asymptomatic cases and because the virus is spreading in developing countries. Rich countries won't want to shell out the trillions that might be needed so the latter can cope with the situation. (And that will translate into yet another migration crisis to boot. Etc. Etc.)
For better or worse, the current lockdown measures in a growing number of countries are only postponing the inevitable mass outbreak by a few weeks. That is, unless countries get their act together and find a huge pot of money to tap into -- and in periods with a collapsing economy, the only sane pot of money to tap into is wealth. I'm not holding my breath.
Till the time widespread testing is ensured (and hospitals have some breather). Then test and isolate the clusters and keep relatively relaxed other "relatively unaffected" areas and not impose full blown lockdown.
...and it would seem logical that the most efficient balance is county-dependent, dependent upon how many are locally infected.
A nationwide hammer seems like it would do lots of economic damage in places that have very few cases.